Which of the following is referred to as the "suicide gland"?

............ support the process of red blood cells formation.

Calcitonin lowers the calcium level in the blood. This is secreted by

Assertion: Hormone calcitonin has an antagonistic effect to that of parathormone.
Reason: Calcitonin decreases blood calcium level while parathormone increases blood calcium level.

$I.$ Regulation of $BMR$
$II.$ Supports the process of $RBC$ formation
$III.$ Controls the metabolism of carbohydrates,proteins and fat
$IV.$ Maintenance of water and electrolyte balance
$V.$ Secretion of $TCT$ hormone
Functions written above belong to which of the following glands?

Which of the following radioactive isotopes is used to detect thyroid cancer?